<html>
	<head>
		<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
		<title>点击按钮出现60秒倒计时的简单js代码(推荐)</title>
	</head>
	<body>
		<input type="button" id="btn" value="免费获取验证码" onclick="settime(this)" />
		<script type="text/javascript">
			var countdown = 60;

			function settime(val) {
				if (countdown == 0) {
					val.removeAttribute("disabled");
					val.value = "免费获取验证码";
					countdown = 60;
				} else {
					val.setAttribute("disabled", true);
					val.value = "重新发送(" + countdown + ")";
					countdown--;
				}
				setTimeout(function() {
					settime(val)
				}, 1000)
			}
		</script>
	</body>
</html>
